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murrsue

Senior Member

1

Sunday, July 12th 2009, 11:45am

Any reason I can't use a $20 flapper check valve for backflow control?

I have 1 1/4" poly pipe coming in from my submersible pump (pressure tested 40-60psi as the pump cycles). I have a large yard approx 190 x 150 with water supply in one corner. I figure I may as well take advantage of the large pipe and run a 1 1/4" poly main feed down the center of the yard (the long way) and branch off of it with pairs of valves going to 9 zones x 5 Rainbird 5004fc's. I figure that way I won't get pressure/flow loss way at the end. The price goes WAY up if I go to a 1 1/4" backflow device and I don't want to restrict it with a 1" one. Any reason I can't just use a 1 1/4" flapper check valve to prevent backflow? They're only $20bucks. I'm not concerned with code being way out in the boonies I just want a backflow device in the system.

Wet_Boots

Supreme Member

Posts: 4,088

Location: Metro NYC

2

Sunday, July 12th 2009, 4:01pm

If you aren't concerned with codes, why bother with anything? Geeez, could you get any more stupid?!!

Almost Heaven

Unregistered

3

Monday, July 13th 2009, 2:36pm

Good question, stupid answer. Or do you have ties to the American brass industry

If you aren't concerned with codes, why bother with anything? Geeez, could you get any more stupid?!!

HooKooDooKu

Supreme Member

4

Monday, July 13th 2009, 3:13pm

If safety is truely your concern, a simple check valve isn't going to hack it.

For starters, there is "stuff" in water... and I'm not talking about germs, I'm talking foreign matter. As a simple example, I have city water, and I installed a filter (because of drip irrigation) for my system. The 1st time I cleaned the filter, there was a stick that looked to be a broken off piece of toothpick. Stuff like that can get wedged into a check valve and prevent it from closing. When that happens, the check valve becomes completely useless. Some would argue that you need to just use double check valves. But the problem there is that trash in water comes in waves, and if something comes along to block one valve, the odds are pretty good that both valves can become stuck at the same time. The next thing is proving your check valves are working. If you buy a duel-check backflow preventer, it's mostly nothing more than a pair of very well designed check valves (i.e. higher quality than $20). But the real key is that is comes with test cocks. With the test cocks, it's possible to PROVE that EACH valve is currently working the way it is supposed to. Solid pipe with a set of check valves has no way of testing that each check valve is working properly, and is working independantly of the other check valve.

Now the simple truth is that a 1" back-flow preventer isn't a "restriction" on your 1-1/4" pipe. The only real difference between a 1-1/4" backflow preventor and a 1" backflow preventor is the amount of water pressure loss through the device (and depending upon the device and flow rate, there are some preventors where the smaller preventor might have less of a pressure loss.

Wet_Boots

Supreme Member

Posts: 4,088

Location: Metro NYC

5

Monday, July 13th 2009, 7:33pm

RE: Good question, stupid answer. Or do you have ties to the American brass industry

If you aren't concerned with codes, why bother with anything? Geeez, could you get any more stupid?!!
Never, ever, validate stupidity. If there's a code, follow it. If there isn't, do yourself a favor and understand that it isn't your water. It belongs to the state. And sooner or later, they will take an interest in safeguarding the supply.

murrsue

Senior Member

6

Thursday, September 10th 2009, 2:38pm

Well I went ahead and bought a 1 1/4" Febco PVB assembly as well as a Febco strainer. I figure they're worth the added expense for the peace of mind I guess. A bit surprised when they arrived both sporty lovely stickers that state they are constructed with materials that may cause cancer. Great.

Wet_Boots

Supreme Member

Posts: 4,088

Location: Metro NYC

7

Thursday, September 10th 2009, 6:01pm

You won't regret taking the precaution, if for no other reason than for being a step ahead of regulations, and not having to rework the system later on.

debo

Active Member

8

Saturday, September 12th 2009, 8:38pm

You won't regret taking the precaution, if for no other reason than for being a step ahead of regulations, and not having to rework the system later on.

debo

Active Member

9

Saturday, September 12th 2009, 8:38pm

You won't regret taking the precaution, if for no other reason than for being a step ahead of regulations, and not having to rework the system later on.

debo

Active Member

10

Saturday, September 12th 2009, 8:40pm

You won't regret taking the precaution, if for no other reason than for being a step ahead of regulations, and not having to rework the system later on.


If you are on your own pump/well with non-drinkable water, why bother with a backflow?...The "down the road is BS". They cannot make you add something to it after the fact..Called grandfathered in..

Codes, are great if you follow them...They are they for people that do not get it.

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